/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.formats.avro;

import org.apache.flink.api.common.functions.RichMapFunction;
import org.apache.flink.api.java.DataSet;
import org.apache.flink.api.java.ExecutionEnvironment;
import org.apache.flink.api.java.tuple.Tuple3;
import org.apache.flink.formats.avro.AvroOutputFormat.Codec;
import org.apache.flink.formats.avro.generated.Colors;
import org.apache.flink.formats.avro.generated.Fixed2;
import org.apache.flink.formats.avro.generated.User;
import org.apache.flink.test.util.JavaProgramTestBase;

import org.apache.avro.file.DataFileReader;
import org.apache.avro.io.DatumReader;
import org.apache.avro.reflect.ReflectDatumReader;
import org.apache.avro.specific.SpecificDatumReader;
import org.junit.Assert;

import java.io.File;
import java.math.BigDecimal;
import java.nio.ByteBuffer;
import java.time.Instant;
import java.time.LocalDate;
import java.time.LocalTime;
import java.time.temporal.ChronoUnit;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Objects;

/**
 * IT cases for the {@link AvroOutputFormat}.
 */
@SuppressWarnings("serial")
public class AvroOutputFormatITCase extends JavaProgramTestBase {

	public static String outputPath1;

	public static String outputPath2;

	public static String inputPath;

	public static String userData = "alice|1|blue\n" +
		"bob|2|red\n" +
		"john|3|yellow\n" +
		"walt|4|black\n";

	@Override
	protected void preSubmit() throws Exception {
		inputPath = createTempFile("user", userData);
		outputPath1 = getTempDirPath("avro_output1");
		outputPath2 = getTempDirPath("avro_output2");
	}

	@Override
	protected void testProgram() throws Exception {
		ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

		DataSet<Tuple3<String, Integer, String>> input = env.readCsvFile(inputPath)
			.fieldDelimiter("|")
			.types(String.class, Integer.class, String.class);

		//output the data with AvroOutputFormat for specific user type
		DataSet<User> specificUser = input.map(new ConvertToUser());
		AvroOutputFormat<User> avroOutputFormat = new AvroOutputFormat<>(User.class);
		avroOutputFormat.setCodec(Codec.SNAPPY); // FLINK-4771: use a codec
		avroOutputFormat.setSchema(User.SCHEMA$); //FLINK-3304: Ensure the OF is properly serializing the schema
		specificUser.write(avroOutputFormat, outputPath1);

		//output the data with AvroOutputFormat for reflect user type
		DataSet<ReflectiveUser> reflectiveUser = specificUser.map(new ConvertToReflective());
		reflectiveUser.write(new AvroOutputFormat<>(ReflectiveUser.class), outputPath2);

		env.execute();
	}

	@Override
	protected void postSubmit() throws Exception {
		//compare result for specific user type
		File [] output1;
		File file1 = asFile(outputPath1);
		if (file1.isDirectory()) {
			output1 = file1.listFiles();
			// check for avro ext in dir.
			for (File avroOutput : Objects.requireNonNull(output1)) {
				Assert.assertTrue("Expect extension '.avro'", avroOutput.toString().endsWith(".avro"));
			}
		} else {
			output1 = new File[] {file1};
		}
		List<String> result1 = new ArrayList<>();
		DatumReader<User> userDatumReader1 = new SpecificDatumReader<>(User.class);
		for (File avroOutput : output1) {

			DataFileReader<User> dataFileReader1 = new DataFileReader<>(avroOutput, userDatumReader1);
			while (dataFileReader1.hasNext()) {
				User user = dataFileReader1.next();
				result1.add(user.getName() + "|" + user.getFavoriteNumber() + "|" + user.getFavoriteColor());
			}
		}
		for (String expectedResult : userData.split("\n")) {
			Assert.assertTrue("expected user " + expectedResult + " not found.", result1.contains(expectedResult));
		}

		//compare result for reflect user type
		File [] output2;
		File file2 = asFile(outputPath2);
		if (file2.isDirectory()) {
			output2 = file2.listFiles();
		} else {
			output2 = new File[] {file2};
		}
		List<String> result2 = new ArrayList<>();
		DatumReader<ReflectiveUser> userDatumReader2 = new ReflectDatumReader<>(ReflectiveUser.class);
		for (File avroOutput : Objects.requireNonNull(output2)) {
			DataFileReader<ReflectiveUser> dataFileReader2 = new DataFileReader<>(avroOutput, userDatumReader2);
			while (dataFileReader2.hasNext()) {
				ReflectiveUser user = dataFileReader2.next();
				result2.add(user.getName() + "|" + user.getFavoriteNumber() + "|" + user.getFavoriteColor());
			}
		}
		for (String expectedResult : userData.split("\n")) {
			Assert.assertTrue("expected user " + expectedResult + " not found.", result2.contains(expectedResult));
		}

	}

	private static final class ConvertToUser extends RichMapFunction<Tuple3<String, Integer, String>, User> {

		@Override
		public User map(Tuple3<String, Integer, String> value) {
			User user = new User();
			user.setName(value.f0);
			user.setFavoriteNumber(value.f1);
			user.setFavoriteColor(value.f2);
			user.setTypeBoolTest(true);
			user.setTypeArrayString(Collections.emptyList());
			user.setTypeArrayBoolean(Collections.emptyList());
			user.setTypeEnum(Colors.BLUE);
			user.setTypeMap(Collections.emptyMap());
			user.setTypeBytes(ByteBuffer.allocate(10));
			user.setTypeDate(LocalDate.parse("2014-03-01"));
			user.setTypeTimeMillis(LocalTime.parse("12:12:12"));
			user.setTypeTimeMicros(LocalTime.ofSecondOfDay(0).plus(123456L, ChronoUnit.MICROS));
			user.setTypeTimestampMillis(Instant.parse("2014-03-01T12:12:12.321Z"));
			user.setTypeTimestampMicros(Instant.ofEpochSecond(0).plus(123456L, ChronoUnit.MICROS));
			// 20.00
			user.setTypeDecimalBytes(ByteBuffer.wrap(BigDecimal.valueOf(2000, 2).unscaledValue().toByteArray()));
			// 20.00
			user.setTypeDecimalFixed(new Fixed2(BigDecimal.valueOf(2000, 2).unscaledValue().toByteArray()));
			return user;
		}
	}

	private static final class ConvertToReflective extends RichMapFunction<User, ReflectiveUser> {

		@Override
		public ReflectiveUser map(User value) {
			return new ReflectiveUser(value.getName().toString(), value.getFavoriteNumber(), value.getFavoriteColor().toString());
		}
	}

	private static class ReflectiveUser {
		private String name;
		private int favoriteNumber;
		private String favoriteColor;

		public ReflectiveUser() {}

		public ReflectiveUser(String name, int favoriteNumber, String favoriteColor) {
			this.name = name;
			this.favoriteNumber = favoriteNumber;
			this.favoriteColor = favoriteColor;
		}

		public String getName() {
			return this.name;
		}

		public String getFavoriteColor() {
			return this.favoriteColor;
		}

		public int getFavoriteNumber() {
			return this.favoriteNumber;
		}
	}
}
